Rotary locator for crankshafts



Feb. 18, 1969 w. E. HAPPEL ROTARY LOCATOR FOR CRANKSHAFTS sheet FiledJan. 21, 1965 TR] 6 CR3 INVENTOR WILLIAM E.H4PPEL ATTORNEY Sheet 2 of 2Feb. 18, 1969 w. E. HAPPEL.

ROTARY LOCATOR FOR CRANKSHAFTS Filed Jan. 21, 1965- I Y will!!!illlllllll v m I: 1] ll I Tirlll {in H rill! L lllllllll'l Winn D If!!!g um l IIIII llllllll INVENTOR WI LLIAM E-HAPPEL BY ATTORNEY UnitedStates Patent 4 Claims ABSTRACT OF THE DISCLOSURE The apparatus of thisapplication is a steady rest used primarily for supporting crankshaftjournals during; a grinding operation. In addition to the'function ofsup porting the crankpin journals during a grinding operation, thedevice also is used to provide a precision rotary location of acrankshaft prior to a grinding operation by effecting a firm contactbetween locating surfaces which locate each crankpin in axial alignmentwith the work drive axis. In order to perform this locating operation tobest advantage, it has been found advisable to use means other than themembers which hold the work engaging shoe against the work during agrinding operation. In this case, the work engaging shoe is mounted onthe erid of a piston-type plunger which is held by means of a spring inengagement with a hydraulically operated actuating wedge. The wedge ismoved endwise to urge the plunger and shoe into engagement with acrankpin during a grinding operation. A separate source of fluid underrelatively low pressure is connected to act directly on the plunger,i.e., independently of the wedge, to urge a work engaging shoe against acrankpin for the rotary locating function. This is a decided improvementover previous devices for performing the same function, none of whichinvolves applying a low pressure directly to the shoe supportingplunger.

This invention relates to grinding machines, particularly machines forgrinding the crankpins of crankshafts, and more particularly, to thesteady rest for supporting said crankpins during a grinding operation.

In an automatic crankpin grinder, the steady rest performs a dualfunction. After automatic rotary indexing of a crankshaft, the crank isgiven an additional turning action to be sure that the locating surfacesare in solid engagement. This function has been performed by advancingthe back rest shoe by the same means which advances it during a grindingoperation. It has been found that the force exerted by the shoe whenactuated in this manner, tends to deflect the crankshaft beyond thepoint where the locating surfaces are in suitable engagement.

The term index as used here relates to the longitudinal and rotarymovement of a crankshaft from the position for grinding one crankpin toa position for grinding the next crankpin, particularly where eachcrankpin is in a different plane or has a dilferent axis.

The term locate relates to a precision operation on a crankshaft afterthe above mentioned index operation has been completed. The locatingfunction involves endwise movement of the crankshaft to effect precisionalignment of the crankpin with the grinding wheel and a slight rotarymovement to insure firm contact between the rotary locating surfaces onthe crankshaft and the co acting locating elements on the face plate orwork drive member.

It is, therefore, an object of the present invention to provide meansfor effecting precision angular location of a crankpin in such a manneras to avoid deflecting the crankshaft.

Another object is to :provide one means to advance a steady rest shoefor effecting precision angular location "Ice of a crankpin and anothermeans for advancing said shoe for, a grinding operation.

Another object is to provide low pressure means for effecting precisionangular location of a crankpin on a crankshaft.

FIG. 1 shows a hydraulic and electric circuit for successively actuatinga steady rest member to effect precision angular location of a crankpinand, thereafter, to support said crankpin for a grinding operation.

FIG. 2 is a partial front elevation, partly in section, showing therelation between the locating pin and the locating hole or notch in theflange.

The invention consists of a frame 10 pivotally mounted at 11 on a base(not shown). Piston and cylinder 21 are suitably mounted to advance andretract frame 10 about its pivot toward and from crankpin W ofcrankshaft C.

The steady rest consists of an upper plunger member 25 slidable in frame10 and having a shoe 26 for engaging crankpin W. A lower supportingmember 30 is pivotally mounted at 31 on frame 10 for movement by anactuating means 32 to engage and support crankpin W from below againstgrinding wheel 15.

. The means for advancing and retracting plunger mem ber 25 and shoe 26consists of a cam member 35 in abutting relation with stub rod 36 ofpiston 37 in cylinder 38. In order to retract plunger member 25, fluidunder pressure must be supplied in the opposite direction to piston 40having an abutment 41 which engages the other end of cam member 35,-shifting said "cam member upwardly and permitting retraction of shoe 26and plunger member 25 by means of spring 27. Plunger member 25 may alsobe actuated by directing fluid under pressure into chamber 28 formed incylinder 38 between pistons 37 and 40. This fluid acts on plunger member25 as a piston to advance shoe 26 to engage crankpin W after saidcrankpin has been indexed, but before it is clamped, to rotate crankpinW about the axis of the crankshaft so as to effect solid engagementbetween the internal surface of hole in crank flange 51 and locating pin52 in index plate 55, which enters hole 50 when crank-pin W is placed inthe machine. On some cranks, the flange is notched to provide a surfacefor engagement by pin 52.

Operation Frame 10 is advanced to horizontal operative position bypiston 20. At this time, steady rest shoe 26 is not in contact withcrankpin W.

Limit switch 4LS is closed when frame 10 places plunger member 25 inhorizontal position, and comletes a circuit to energize control relay4CR and timer relay TR.

Timer relay contact TR1 closes in the circuit to valve solenoid 3.

Control relay contact 4CR1 closes to energize control relay 6CR.

Control relay contacts 6CR1 and 6CR2 close a circuit through previouslyclosed timer relay contact TR1 to energize valve solenoid 3.

Valve is shifted to the right against spring 61 to direct fluid underpressure from the pump through a pressure reducing valve 62 to chamber28 to apply a relatively low pressure to cause plunger member 25 toengage and rotate crank-pin W about the axis of the crankshaft C to urgeone side of hole 50 in crank flange 51 against locating pin 52.

The purpose of timer relay TR is to permit angular location to becompleted before axial location takes place. When timer relay TR timesout, timer relay contact TR1 opens, deenergizing control relay 6CR andvalve solenoid 3. Valve 60 is shifted to the left by spring 61,

dropping the pressure on plunger member 25 which is then retracted byspring 27.

After a predetermined grinding operation, shoe 26 is advanced to supportthe crankpin for a grinding operation. In order to accomplish this,relay contacts 40CR1 and 40CR2 are actuated by a suitable size controlrelay (not shown) to complete a circuit to energize valve solenoid 12.

Valve 65 is shifted by valve solenoid 12 to the right against spring 66to direct fluid under high pressure to the upper end of cylinder 38,urging piston 37 downwardly against cam member 35. Cam member 35advances plunger member 25 to engage crankpin W with greater force thanfor angular locating of crankpin W, for a grinding operation.

At the end of a grinding operation, relay contacts 40CR1 and 40CR2 areopened, deenergizing solenoid 12 which is shifted to the left by spring66 to direct fluid under pressure to the lower end of cylinder 38. Saidfluid under pressure urges piston 40 and abutment 41 against cam member35 to reset said cam member and permit spring 27 to retract plungermember 25 and shoe 26.

I claim:

1. A device for elfecting precision rotary location of a crankshaft in acrank grinding machine comprising (a) means for rotatably supporting acrankshaft for rotation about an axis coinciding with the axis ofacrank-pin,

(b) co-acting locating surfaces on said crankshaft and said supportingmeans,

(c) a steady rest frame pivotally mounted for movement toward and fromwork supporting position,

(d) a plunger slidably mounted in said frame,

(e) a work rest shoe on one end of said plunger,

(f) positive means operable after said frame is in said work supportingposition for advancing said plunger relative to said frame to support aworkpiece during a grinding operation,

(g) and means for effecting firm contact between said co-acting surfacescomprising means operable independently of and prior to operation ofsaid positive means and while said frame is in said work supportingposition to advance said plunger relative to said frame for applying aturning force to said crankshaft less than the force applied by saidpositive means.

2. Apparatus of claim 1 in which the means for applying a turning forceto said crankshaft is a supply of fiuid under pressure, connected to actdirectly against the other end of said plunger.

3. Apparatus of claim 2 in which a timer energized when said frame movesto work supporting position, times out to disconnect said fluid underpressure from said plunger.

4. Apparatus of claim 1 in which yielding means is provided for holdingsaid plunger in retracted position.

References Cited UNITED STATES PATENTS 1,961,091 5/1934 Smith.

2,099,161 11/1937 Leeuw 5l238 X 2,638,719 5/1953 Balsiger 51-238 X2,655,828 10/1953 Hazen.

3,118,258 1/1964 Price et a1. 51--238 X 3,233,368 2/1966 Price 51238 X3,041,792 7/1962 LaFleur 51-237 X HAROLD D. WHITEHEAD, Primary Examiner.

US. Cl. X.R.

